量研学術機関リポジトリ「QST-Repository」は、国立研究開発法人 量子科学技術研究開発機構に所属する職員等が生み出した学術成果(学会誌発表論文、学会発表、研究開発報告書、特許等)を集積しインターネット上で広く公開するサービスです。 Welcome to QST-Repository where we accumulates and discloses the academic research results(Journal Publications, Conference presentation, Research and Development Report, Patent, etc.) of the members of National Institutes for Quantum and Radiological Science and Technology.
Thank you very much for using our website. On the 11th of March 2019, this site was moved from our own network server to the JAIRO Cloud network server. If you previously bookmarked this site, that bookmark will no longer work. We would be grateful if you could bookmark the website again. Thank you very much for your understanding and cooperation.
Introduction
In recent years, there has been an increasing demand of ultra-trace determination of radionuclides in studies of nuclear emergency preparedness, nuclear decommissioning, safeguards and nuclear forensics, and in environmental studies, such as tracing the sources of radioactive contamination, revealing the transport process of aerosols in the atmosphere, and in study of the ongoing environmental changes. ICP-MS, as an atom-counting approach that counts the atoms themselves, irrespective of their decay mode, specific activity, or half-life, is gradually replacing/has replaced conventional radiometric methods, especially, due to its high abundance sensitivity and the ability of removal of polyatomic interference via ion-molecular reaction in the reaction cell, the triple quadrupole ICP-MS (ICP-MS/MS) showed great potential for ultra-sensitive analysis of actinides. In this work, we presented a determination method of ultra-sensitive determination of Pu isotopes in environmental samples by ICP-MS/MS with a high efficiency sample introduction system.
\nMethod
In this method, the ICP-MS/MS (Agilent 8800) combined with an APEX-Q high efficiency sample introduction system (Elemental Scientific Inc, Omaha, NE, USA) was used for the analysis of Pu isotopes (239Pu, 240Pu and 241Pu). An established chemical separation method involving HNO3-HF digestion, CaF2/LaF3 co-precipitation and extraction chromatography (TEVA-UTEVA-DGA) separation was used for the separation of Pu from U, Th and other interferences [1].
\nResults and discussion
In order to achieve the ultra-sensitive analysis of Pu isotopes, we evaluated the sensitivity of ICP-MS/MS at three no-gas modes using a U standard solution (1 ng/ml): (1) Single MS; (2) MS/MS and (3) APEX-MS/MS. Fig. 1 showed the obtained sensitivity and comparison with that of sector-field ICP-MS (SF-ICP-MS). A factor of 7 sensitivity improvement was achieved using APEX-MS/MS mode. The estimated instrumental detection limit ranged from 0.05 to 0.29 fg/ml for Pu isotopes (239Pu, 240Pu and 241Pu), which is comparable to that of APEX-SF-ICP-MS [2]. The UH+ formation was found at 4x10-5 level. The method was validated by analysis of sediment reference materials.
\nReferences
1. Z. Wang, J. Zheng, Y. Ni, W. Men, K. Tagami, S. Uchida, Anal. Chem. 89, 2221-2226 (2017).
2. J. Zheng, M. Yamada, Talanta, 69, 1246-1253 (2006).